Miller 625 cutting issues please help

Someone please help… I’m pulling my hair out. I’m having terrible cut quality. I got all new consumables and clean air. The torch will be cutting just fine then out of no where it acts like it looses ground and stops penetrating the steel (16ga hr). The ground is clamped to the steel sheet, and I have the steel clamped down. I’m running it at approximately 25-27 amps at 80 ipm. I attached a photo so u can see what I’m fighting. image|450x500

Turn up the amps? It looks like its still on just not cutting through.

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Thanks for the replay. So I tried cranking up the amps and even slowing down the ipm and nothing. It acts as if I took the ground off and it just sputters. Plus I wouldn’t think I would need 40 amps to cut 16 gauge steel. It’s frustrating.

You have the older Miller 625, not the newer 625 Extreme?

I got the newer extreme

Ok, are you using the drag cup or machine cup? Have a water trap right at the machine? Water in the lines can interupt a cut like that.

I have a water trap at the air compressor and their is a water trap inside the Miller I found when I wired it. Both are dry. I live in Colorado and it’s been super dry lately. I tried the standard deflector shield and the drag shield with the same result. image|375x500

What does your consumables and swirl ring look like? Have you used this machine to cut steel by hand? Have you tried it recently to see if it the machine or the table?

And where are you grounding the machine? Right on the work piece?

I replaced the consumables today, the swirl ring looks good and the electrode rebounds when I push on it. I haven’t hand cut with it for a bit. I can try it tomorrow ( wife and baby are already sleeping). For the table I checked and made sure the gantry is level across both the x and y. I wonder if the oxidation on the hot rolled steel is not giving me a good ground? I wouldn’t think It would be an issue but I can’t think of anything else.

Ya I was grounding on the table then I started grounding straight to the metal with the same frustration results. I’m gonna definitely make the scrap guy happy this week

Seems like you got it all covered. Try the manual cut when you get a chance. Your pic certainly doesn’t look like the machine is shutting off but dropping power somehow.

Good solid power to the cutters plug? And good ground at the plug? Check the receptacle connections too.

Lastly, could the amp pot on the machine be weak or have a bad spot possibly?

The wiring is 220 and solid. I didn’t think of the amp pot. That could possibly be the issues, But it cuts good for a minute then it sputters then it’ll cut good again. I wonder if it’s a bad batch of consumables idk? Might be buying a hypertherm sooner then I thought lol…

Btw I really appreciate all your feed back and info.

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I had the pot go bad on my welder, it acted the same way. After checking everything 10x over, it was the only piece of the puzzle. Easily fixed. I almost got rid of the machine due to frustration. Still my favorite.

I’ll crank out a bunch of hand cutting tomorrow with some scrap steel and see how it acts.

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I had the same issues at one point with my 625ex.
All my problems went away with a new swirl ring, there is no such thing as “the swirl ring looks good” you can not see the problems with it. Just walk away untill you have a new one to put in, they are cheap and can save you alot of frustration.
Hope you get it cutting well soon.
Good luck!


Thanks for the info. I’ll order a new swirl ring and give it a shot.

It will be your best bet at this point, the swirl ring sets the shape of the cone of cutting area. When hand cutting with a drag shield the cone is not very important because your right against the material, when cutting on the crossfire your off the surface a few thousands and you need the cone focused the way it is designed to be or it will not cut so well. It is hard to believe that air passing through the swirl ring will wear it out but it does just enough to change that cone and you cant see the minute difference in the holes.

Good luck man!


So after checking everything 200 times it was the swirl ring in the end causing all the problems. I just cut 3 large signs with no problems, back to making money. I appreciate all the info and help on this gentleman. I would have never thought the swirl ring was the issue. Definitely gonna get some spares to keep on hand now.